Centrifugal separator



Aug. 4, 1953 H. R. DRURY CENTRIFUGAL SEPARATOR 2 Sheets-Sheet 1 FiledJune 2, 1950 Aug. 4, 1953 H. R. DRURY 2,647,686 CENTRIFUGAL SEPARATORFiled June 2, 1950 '2 Sheets-Sheet 2 Patented Aug. 4, 1953 UNITED STATESFATENT OFFICE CENTRIFUGAL SEPARATOR Herbert R. Drury, Laguna Beach,Calif. Application June 2, 1950, Serial N 0. 165,629

1 Claim.

This invention relates to centrifugal separating devices and moreparticularly to separating apparatus employed by miners in theseparation of precious or valuable metals from the substances bearingthe metals and to such apparatus employing a rotating bowl for impartingcentrifugal action to the substance under treatment.

It is among the objects of this invention to provide centrifugalseparating apparatus whereby valuable metals may be efficiently,economically separated from alluvium or gangue, placer =grave1s and sandor mine residue, particularly from such material containing black sand(magnetite) and muck (decomposed quartz) which has seriously interferedwith separation as performed in prior concentrating bowls.

Another object of the invention is to provide a centrifugal separatingbowl which is particularly adaptable to the recovery of fine gold,platinum or other valuable metals from gangue and the like.

Another object of the invention is to provide in a centrifugalseparating bowl means for thoroughly working the metal containingsubstance under treatment as it moves over the surface of the bowl andseparate means for entrapping and holding the precious metals separatedfrom the substance as it is being so worked.

A still further object of the invention is to provide a centrifugalseparating bowl having a substantially smooth inner surface, a mesh-likeliner arranged in said bowl in spaced relation to the inner surfacethereof and means disposed between said l ner and the inner surface ofthe bowl for entrapping and retaining particles of gold and otherprecious or valuable metals as they are separated from the materialtreated in the bowl.

A still further object of the invention is to provide a novel liner fora centrifugal separator which serves to efiiciently and economicallyseparate and retain precious metals from gangue which liner may beeasily removed from the separator and cleaned to recover the preciousmetal.

These and other objects and advantageous features of the invention notat this time more particularly pointed out will become more apparent asthe nature of the invention is better understood from the followingdetailed description taken in conjunction with the accompanying drawingwherein like reference characters denote corresponding parts, andwherein:

Figure l is a fragmentary top plan view of a centrifugal separatorembodying the present invention,

Figure 2 is a transverse sectional view taken on the line 22 of Figurel,

Figure 3 is an enlarged sectional detail of the preferred linerconstruction,

Figure 4 is an enlarged sectional detail view of a modified form ofliner, and,

Figure 5 is a side elevational view of the device with certain partomitted.

With reference to the accompanying drawings, there is illustratedcentrifugal separating apparatus embodying the teachings of the presentinvention comprising a base frame I including side frame members II andend frame members l2 the adjacent ends of which are mitered and weldedtogether to form a unit. Extending between the end frame members l2 area pair of spaced angle irons l3 upon which is disposed a supportingplate l4 positioned at the center of the frame In. Mounted on the platel4 and secured to the angle irons I3, is an upstanding journal boxmember formed with an internal axial bore IS.

The journal member l5 supports in the bore I 6 thereof a verticallydisposed shaft l8 rotatably mounted in a thrust bearing l1 on the uppersurface of the journal l5. Keyed to the shaft l8 above the bearing l! isa sheave I9 the purpose of which will be described hereinafter. Theupper end of the shaft is extends into the bore of a depending hub 2|formed on the lower surface of a supporting disk 22 and is securedthereto by means of set screws 23. Supported on the top surface of thedisk 22 is a frusto conical concentratin bowl 24 preferably made ofaluminum, iron, steel, plastic, or of molded hard rubber if desired. Thebowl 24 is secured to the disk 22 for rotation therewith by means ofsuitable bolts 25.

The apparatus for rotating the bowl 24 and the supporting structuretherefor is best illustrated in Figures 2 and 5 of the drawings andincludes a motor 26 mounted on a plate 21 supported between spaced anglemembers 28 secured to the frame l0. Although an electric motor isillustrated in the drawing, any other suitable power means may beemployed depending upon the particular site where the device is to beset up and used. Extending parallel to the drive shaft 28 of the motoris a countershaft 30 suitably supported in spaced brackets 3| and 32mounted on the frame ID. A belt 33 operatively connects pulley 34, keyedto the end of the countershaft, to pulley 35 on the motor shaft 29.Mounted on the countershaft 30 is a sheave 36 which is aligned with andis adapted to drive the sheave IQ of the bowl supporting assemblythrough the belt 31.

The bowl 24 is preferably frusto conical in configuration being formedwith a smooth interior surface, with the base thereof resting on theupper surface of the disk 22. The side wall of the bowl may extend at anangle of between fifty and sixty degrees to the plane of the base,however, it has been found that if the pitch of the side wallisapproximately fifty-eight degrees with respect to the base, the metalcarrying material introduced into the bowl is properly worked as itpasses upwardly along the side wall of the device and maximum separationis obtained before it-is discharged from the bowl. Furthermore maximumspeed of operation and capacity isobtained with the aforesaid angulationof the side wall.

Mounted in the bowl 24 so as to substantially cover the entire innerwall surface thereof is. a frusto conical liner or basket 40, the wallportion dzl-zofwhich is suitably constructed of wire mesh, or expandedmetal with the lower portion thereof beingwelded orotherwise-secured toa base plate 42 which rests on the-base 38 of the bowl. The upper. edgeof the wall portion 4.! terminates in and is secured to a ring. whichsets within the peripheral edgeportionof thebowl. The basket 40 whichserves to create aturbulence in the water which carries the -materialintroduced into the bowl-as it passes thereacross, and to hold thefabric closely against the bowl, is held in position. by. means ofbolts, 44 extending through the apertures 45, the latter serving asdrain ports when thebolts M are removed therefrom. Disposed between thewire mesh basket Ml and the interior wall-oi the'bowl, 24 is a coveringor bag t! made-of a; suitable fabric material such as burlap or blanketmaterial. This covering serves toentrapand hold the particlesof preciousmetal separated from thematerial treated inthe bowl. Irr-Fignre 4 thereis. illustrated a modified form of basket in which the wire mesh 4!comprising the side wall thereof is replaced by expanded metal-50.

A circular launder l' is coaxially positioned aboutthezrim ofthe-discharge'edge of'the bowl. The launder- 5| includes, an outercylindrical wall 52, an inner cylindrical wall 53 and a fiat inclinedbottom 54"thus forming an asymmetrical annular chamber. 'A rectangulardischarge chute 55 is provided adjacent the lower portion of the bottom54'. The walls, bottom and chute are. suitably secured together as byWelding to form a complete unit. The launder is supported by a pluralityof angle brackets 56" bolted or otherwise secured to members 51extending-upwardly from the base In. The bowl is fed from a feed chute58 which opens to the interior of the bowl adjacent the bottom thereof.A suitable bracket 59 supported bythe members 51' serves to maintain thechute 58 in proper position within the bowl.

In using the concentrating bowl of the present invention the gangue orconglomeration of variousxmetallic substances and associated substances,such as placer gravel or sand mixed with sufficient water to carry it,is introduced intothebowl 24 through the feed chute 58 and deposited inthe bottom of the bowl. The bowl is rotated so as to cause the mixtureto travel outwardly and upwardly over the surface of the wire meshbasket or liner 50. I have found that where a bowl with a diameter ofthirty-six inches is used, a speed of about two hundred R. P. M. ispreferable. The rotation of the bowl creates a centrifugal force whichworks the mixtnre against the surface of the liner effecting a continualturmoil as it moves upwardly thereover causing the heavy desirablemineral particles to move outwardly through the wire mesh 4! where theybecome entrapped in the fabric liner 41 disposed between the wire-meshbasket and the inner surface of the bowl. This action continues untilthe fabric liner 41 has become fairly well saturated with the preciousmetal at which time the feed of solid substance is first cut off,andthen rotation of the bowl is stopped. The drain plugs 45 are removedand the water is permitted to drain out of the bowl into suitablereceptacles. The wire basket is removed from thebowl. after. which thefabric liner or bag is carefully washed to remove therefrom the gold orother precious metal particles which have been entrapped therein.

Having thus described my invention so that those skilled in the art maypractice the same, what I desire to obtain by Letters Patent isdefinedin the appended claim.

I claim:

A centrifugal separator comprising a frustoconical bowl for receivingmaterials to be treated including a base and a side wall, means forrotating said bowl at high speed, a. fabric covering disposed againstthe inner side wall surface of the bowl, a removable frustoconicalbasket complemental to the inner surface of the bowl and adapted to bereceived therein, said basket including a base plate arrangedto seat onthe base of the bowl and be secured thereto, a ringxmember arranged toengage within the peripheral edge of the bowl and open mesh materialspanning the space between the peripheral. edge of said'base plate andsaid ring adapted. to maintain said fabric covering against the innerside wall of the bowl, said basket serving to keep the material treatedin the bowl in a fluid condition whereby centrifugal force classifiesand separates the heavier particles moving them through the wall of thebasket where they become entrapped in the fabric covering on the bowlwall.

HERBERT R. DRURY.

References Cited in the file of this patent UNITED STATES PATENTS

